Before the deposition on the Er:Al2O3 Lively material, the coupling circuit, i.e., the strip waveguides, the mode transition tapers plus the manner converters were protected with a 800 nm thick layer of hydrogen silsesquioxane (HSQ, n ~1.45) to avoid their coating While using the Lively material, as shown in Fig. https://francesc085uah0.wikiinside.com/user